Under Armour said Thursday that data from 150 million diet and fitness app MyFitnessPal accounts were compromised, helping to send shares down by 3% in the sportswear apparel maker during trading after hours.
The data stolen from the accounts includes email addresses, user names and passwords that are scrambled, for the popular website and mobile app MyFitnessPal, said Under Armour in a prepared statement. Driver’s license numbers, payment card information and social security numbers were not compromised the statement said.
This is the largest breach of data in 2018 and one of the top five ever, based upon the number of compromised records.
The larger hacks include three billion accounts at Yahoo compromised during 2013 and credentials of over 412 million adult websites users in 2016.
Under Armour announced that it was working with law enforcement and security firms that specialize in data breaches, but did not give any details about how hackers had entered the network or pulled data out without being caught doing so.
While this breach did not contain any financial data, the large amount of email addresses stolen is valuable to the cyber criminals who made off with them.
Email addresses that were retrieved during an attack in 2014 that compromised the data of more than 83 million Customers of JPMorgan Chase was later used in schemes of pump-and-dump to boost the prices of stocks, says federal indictments in the U.S. in the 2015 case.
Under Armour announced in one of its alerts on its official website that it would require users of MyFitnessPal to change account passwords, and urged its users to do it immediately.
The company alert said the security team was continuing to monitor for any suspicious activity and coordinate with authorities in law enforcement and that it was increasing the systems it has that detect as well as prevent access that is unauthorized to user data.
Under Armour has said that it started to notify its users of the breach Thursday, four days after first learning itself of the data breach.
In 2015, Under Armour acquired MyFitnessPal at the price of $475 million. MyFitnessPay remains part of Under Armour’s connected fitness division that had revenues in 2017 that represent 1.8% of the total sales of more than $5 billion for Under Armour.